how to use icon in Ant-design/icons with V4 - reactjs

Question

I have tried to make a menu, so i create a menuList to config the menu with getMenuNodes(), but Ant framework has been upgraded from v3 to v4 which the icon method has been changed. they are now using icon={<PieChartOutlined />} to instead of icon='PieChartOutlined', everything is working well, the icon area shows the word <PieChartOutlined />right now. i do not know why it happened, please help me to solve this problem.
left-navigation.js
import React, { Component } from 'react';
import { Link } from 'react-router-dom';
import logo from '../../assets/images/logo.png';
import './index.less';
import { Menu } from 'antd';
import { PieChartOutlined } from '#ant-design/icons';
import menuList from '../../config/menuConfig';
const { SubMenu } = Menu;
export default class LeftNav extends Component {
getMenuNodes = menuList => {
return menuList.map(item => {
if (!item.children) {
return (
<Menu.Item key={item.key} icon={item.icon}>
<Link to={item.key}>{item.title}</Link>
</Menu.Item>
);
} else {
return (
<SubMenu key={item.key} icon={item.icon} title={item.title}>
{this.getMenuNodes(item.children)}
</SubMenu>
);
}
});
};
render() {
return (
<div className="left-nav">
<Link to="./" className="left-nav-header">
<img src={logo} alt="" />
<h1>Backend System</h1>
</Link>
<Menu
mode="inline"
theme="dark"
>
{this.getMenuNodes(menuList)}
</Menu>
</div>
);
}
}
menuList.js
const menuList = [
{
title: 'Home',
key: '/home',
icon: '<PieChartOutlined />',
},
{
title: 'Item',
key: '/products',
icon: '<PieChartOutlined />',
children: [
{
title: 'Category Control',
key: '/category',
icon: '<PieChartOutlined />',
},
{
title: 'Product Control',
key: '/product',
icon: '<PieChartOutlined />',
},
],
},
{
title: 'User Control',
key: '/user',
icon: '<PieChartOutlined />',
},
{
title: 'Role Control',
key: '/role',
icon: '<PieChartOutlined />',
},
{
title: 'Diagram',
key: '/charts',
icon: '<PieChartOutlined />',
children: [
{
title: 'Bar',
key: '/charts/bar',
icon: '<PieChartOutlined />',
},
{
title: 'Line',
key: '/charts/line',
icon: '<PieChartOutlined />',
},
{
title: 'Pie',
key: '/charts/pie',
icon: '<PieChartOutlined />',
},
],
},
];
export default menuList;

Answer 1

You are passing a string of '<PieChartOutlined />', you need to pass the component directly.
import { PieChartOutlined } from '#ant-design/icons';
and:
{
title: 'Product Control',
key: '/product',
icon: <PieChartOutlined />,
},
You'll need to install ant-design/icons if you haven't already:
npm install --save #ant-design/icons

Answer 2

Since reason performance on the previous version, antd team was apply tree-shaking to use icon. More detail, you can check https://ant.design/docs/react/migration-v4